Power Door Locks Possessed?
 

So, this past winter, my wife & I were dropping off some "stuff" at my daughter's house, a cold, dark evening, so I left my 2003 F150 running with the heat on while we were unloading. Not five minutes later, the doors were locked & we couldn't get in. Naturally, I blamed my wife, thinking she must have hit the lock button when she got out. Just yesterday, I left it running in my driveway while I got out to move something in the garage, & again,the doors locked themselves pretty much right away! What in the hell is going on here?????

Welcome to GEM's-ville. Many of the 97-03 members have been there, myself included on my old '02. Feel free to search General Electronics Module.

Cliffs Notes: windshield is leaking onto the GEM under the left side of the dash. Causes all kinds of electrical gremlins. I'd bet that if you push on the upper corners of the windshield, it'll move. The main correct option is to pull the windshield and reseal it, then address the GEM. A rice container and a day or two should dry it out well enough. Apply dielectric grease to the connector afterwards. If removal of the windshield isn't a financial option, take foaming carpet cleaner and spray the outside edges of the windshield all the way around and use an air compressor inside all the way around. This will allow you to pin point your leaking area. Address that as you see fit and then address the GEM in the same manner I address above.

Lenn....use a small open container and put some Damprid in it. It comes scented or non-scented versions. It is a charcoal absorbent, and is cheap. You can get it at Lowes or Home Depot for $4. for a 32 oz bag. I use it in my closets also. It gives off a nice smell and keeps any kind of moisture down to a minimum.

Right, the GEM. The GEM will also trigger the doors if the battery is low or has a bad cell.

From your owners manual

Autolock (if equipped) This feature will automatically lock all the doors when: • all the doors are closed, • the ignition key is in the ON position, • the gearshift lever is shifted into R reverse or a forward gear and • the brake pedal is released. This feature will also automatically relock all the doors when: • the ignition is running and any door is opened then closed, and • you put the vehicle in motion by releasing the brake pedal.

You can also disable the autolock feature- there is a post here somewhere- i used it to disable mine. Try a search for it, cause i cant remember where it was.

This sounds exactly like my issue, thanks!

Time to go on a search, thanks!